Electromagnetic relay.



E. B. CRAFT.

ELECTROMAGNETIC RELAY.

APPLICATION FILED SEPT129, 1910.

1,156,671. Patented 001. 12, 1915.

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UNITED STATES PATENT OFFICE.

EDWARDB. CRAFT, OF HACKENSACK, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.

ELECTROMAGNETIC RELAY.

Application filed September 29, 1910.

To all whom it may concern:

'- State of New Jersey, have invented a certain new and useful Improvement in Electro- 'magnetic Relays, of which the following is a full, clear, concise, and exact description.

My invention relates to electromagnetic relays and has for its object to provide a highly efiicient relay of compact compass and positive operation, having comparatively few parts which may be easily made and readily assembled, and which will not be liable to derangement or failure.

It is a further object of my invention to provide a relay in which the operating parts are readily accessible, but is at the same time of compact and convenient size and dimensions.

My invention therefore involves a novel and improved electromagnetic relay having a'flat core and a fiat armature cooperating witheach other and so mounted with respect to each other that the armature lies substantially in the. plane of the core. Such armature may be of U-shaped or bilateral form and mounted with relation to the core .in such a manner that a substantially comtively-free end of the armature. In the preferred form of my invention the armature is mounted at its extremities upon a rear- 1 Ward extension of the core to lie substantially in the same plane as the core, and to have its free or intermediate portion contiguous to a forward projection of the core.

7 My invention further involves an electromagnetic relay in which a rearward extension of the core forms the supporting means for the entire structure, and also by means of lateral lugs upon said extension supports the armature, the circuit terminals of the coil and the circuit terminal springs adapted to be opened and closed by the movement of the armature.

Another feature of my invention involves an arrangement wherein the usual insulating head upon the energizing coil of the relay serves as a stop for the longitudinally positioned circuit terminal springs extending from their rearward support along the side or sides of the coil.

The electromagnetic relay embodying my Specification of Letters Patent.

Patented Oct. 12, 1915.

Serial No. 584,456.

invention forms a very compact, highly efficient, and extremely simple device. Not only does its small size readily adapt it for many uses but its symmetrical and rectilineal form renders it particularly useful where the space occupied is an important factor. It may furthermore be formed of metal punchings doing away to a large extent with the necessity of expensive tools and labor, and yet such punchings are so arranged in the assembled relay that any slight variations in their dimensions which may exist will not affect the sensitiveness or operation of the relay.

A. relay embodying my invention has been found to respond quickly and positively to minimum current, to release uniformly when ole-energized, and to require but little or no attention in the way of maintenance.

Referring now to the drawings which show a relay embodying my invention Figure 1 is a plan view of a relay embodying my invention; Figs. 2, 3 and 4 show-fdetails of the armature of the relay shown in Fig. 1 and its mounting; Fig. 5 is a sectional view of the relay shown in Fig. 1 taken on the line 55; Fig. 6 is a front view of the relay shown in Fig. 1; Fig. 7 is an enlarged sectional. detail of the mounting of the armature, contact springs, etc., taken on the line 77 of Fig. 1. Fig. 8 is a perspective view of the core and insulation heads, all other parts being removed.

' Like reference characters refer to similar parts in all the figures of the drawings.

The relay embodying my invention is shown as comprising the coil 1 forming an oblate winding upon a flat core 2, and retained upon said core by the insulation heads 3, 4.. The core 2, which may be and is preferably punched magnetic metal, has a rearwardly extending portion 5 which is provided with the upwardly and clownwardly extending lugs 6, by means of which lugs. which are provided with screw holes as will be noted, the relay structure is adapted to be securely fastened to its support. The rearwardly extending portion 5 of the core is also provided with the wings 7 7. Supported by the wings 7, 7 by means of the spring plate 8, is the armature 9. This armature 9 comprises a transverse portion 10 and the two longitudinal arms 11, 11, and is also formed preferably of punched magnetic metal. These longitudinal arms 11, 11

are suitably fastened to the lugs 12, 12 upon the spring plate 8. iiiounted also upon the wings '7 or the rearwardly extending portion 5 of the core, insulated therefrom and from the armature, are the circuit terminal springs 13, 14;, 15, 16, and also the terminal posts 24:, 25 connected to the coil 1. These terminal springs extend longitudinally of the coil and lie above and below the longitudinal arms 11, 11 of the armature. As will be observed from the drawings, the terminal spring 13 is secured so as to lie on one side of the armature, while the terminal spring 1-5: is mounted to lie upon the other side of the armature. These terminal springs at their extreme ends are bent inwardly to ward one another and are provided with the usual contact points to complete the circuit between them. Carried by the armature betweei these springs at the points where the lcngi udinal arms join the transverse portion of the armature are the insulating projections 17 17. These projections 17, 17 serve, when the armature is moved, to open the contact between the springs 13 and 1d and the springs 15 and 16 respectively, it being noted that the arrangement of the springs 15 and 16 is the same as that described tor the springs 13 and 14-. lhe transverse portion 10 of the armature is adapted to overlie a forwardly projecting portion 18 ot the core 2, which carries upon it the screw 19 and the nut 20, serving together to limit the movement of the armature away from the forwardly projecting portion 18 of the core.

in the operation of the relay embodying my invention, the passage of current through the coil 1 causes the transverse portion of the armature to be attracted by the forwardly projecting portion of the core so that the forward or -free portion of the ar mature is drawn down against the forwardly projecting portion of the core and the in sulating projections 17, 17 move the contact springs 1e and 16 out of contact with the contact springs 13 and 15. It will be noted that the magnetic circuit formed by the core with its projections and the armature with its longitudinally extending arms may be made substantially complete except for the normal air gap between the transverse portion 10 of the armature and the forwardly projecting portion 18 of the core. By reason of this, the relay is extremely sensitive and operates eliiciently with current of low voltage. it will be further noted that the contact springs are extremely long compared to the total dimensions of the relay, and are therefore sensitive and positive in their operation, the armature acting upon them substantially at their free ends. It will be further noted that the relay is readily assembled and that all of the parts are readily accessible. Furthermore, that if desired, the

contact springs shown in the drawings hereof may have substituted therefor suitable springs in which he circuit may be closed upon the movement of the armature rather than opened as in the case oi those shown herein. ilpon the cessation of current flowing through the coil the armature will be rel ased, and due to the tension of the con tact springs 11 and 16, or the tension of the spring plate 8, or both, will be retracted to permit the contact springs 13 and 11 and contact springs 15 and 16 to again close. Upon the movement of the armature from its normal position, in which movement the springs 1-1 and 16 are moved out of contact with the springs 13 and 15, these springs 13 and 15 are prevented from following the springs 1 1 and in their movement with the armature by means of the lugs 21, 22, provided respectively upon the springs 13 and 15 which cooperate with the notched corners 23, 23, upon the front insulation head 3 of the coil.

t should be noted that the spring p is made of brass in order hat the m1 circuit may not be absolutely closed when the armature is in its attracted position. The armature should be mounted by means of this spring plate with its ends almost but not quite in contact with the wing The distance between th ends oi the armature and the wings may be varied in various cmbodiments of my invention in view of the particular purposes for which they are to be used. For example, it it is desired that the relay should be particularly sensitive to the energization of the coil and core, the armature should be mounted that its ends are very close to the wings 7. but it it is desired that the relay should be particularly sensitive to the deenergization of the coil and core, the armature should be so mounted that a substantial air gap exists between the ends of th armature and the wings.

Any of the ordinary means may be pro vided for preventing the armature from sticking in its attracted position to the forward projection of the core. but I prefer to accomplish this either by sherardizing the core and armature or by providing the usual brass or copper inserts between the core and armature.

While I have shown one form of my invention and have shown therein one arrangement of circuit terminal springs, it must be understood that my invention is not limited to the form or arrangement shown herein, nor to any particular :t'orm. or arrangement, but is limited only so far as is expressed in the hereinafter appended claims.

Having described my invention what I claim and desire to secure by Letters Patent of the United States is:

1. An electromagnetic relay comprising a sions, a coil about said core, a flat U-shaped armature mounted on said rearward extension and embracing said coil, said armature having its free end contiguous to said forward extension and contact springs also mounted on said rearward extension, said contact springs being controlled by said armature.

3. An electromagnetic relay comprising a fiat core, a flat armature mounted upon a rearward extension of said core and having its free end contiguous to a forward exten sion of said core, said core and said armature being arranged flatwise in substantially the same plane, and said armature constituting a return pole piece between the forward and rearward extensions of said core and forming therewith a substantially complete magnetic circuit.

4. An electromagnetic relay having a fiat core, and a fiat armature extending along two sides of said core, said armature being mounted upon a rearward extension of said core and constituting return pole pieces for the forward and rearward extensions of said core, said core and said armature being arranged flatwise in substantially the same plane.

5. An electromagnetic relay comprising a flat core and a flat flexibly mounted U-shaped armature, said core and said armature be ing arranged flatwise in substantially the same plane.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

6. An electromagnetic relay comprising a flat core, and a flat U-shaped armature mounted upon a rearward extension of said core and having its free end contiguous to a forward extension of said core, said core and said armature being arranged fiatwise in substantially the same plane.

7. An electromagnetic relay comprising a flat core, a coil upon said core, supporting means at the rear of said coil connected to said core, a flat Ushaped armature mounted at its extremities on said supporting means and lying substantially in the plane of said core, a forward extension on said core contiguous the intermediate or free portion of said armature and stop means carried by said forward extension for limiting th movement of said armature.

8. An electromagnetic relay comprising a core, a coil on said core, an armature, contact springs controlled by said armature having lugs thereon, and an insulation head on said coil adapted to cooperate with said lugs to limit the movement of said contact springs under the control of said armature.

9. An electromagnetic relay comprising a core, a coil on said core, a fiat U-shaped armature mounted on a rearward extension of said core and embracing said coil, the side portions of said armature extending longitudinally along the sides of said coil, and contact springs also mounted on the rearward extension of said core over and underlving the side portions of said armature and controlled thereby.

In witness whereof, I hereunto subscribe my name this 27th day of September A. D.,

EDWARD B. CRAFT. Witnesses:

IRVING MACDONALD, MORGAN WVAsHBURN, Jr.

Washington, .D. O." 

